Last year, when Elon Musk’s Tesla Inc. bought solar-panel installer SolarCity for $2 billion, many critics mocked that both companies had no synergies.

However only a year later, in times when subsidies for solar have gone through the floor, more and more solar installers are looking to partner with bigger established companies to find customers. According to Bloomberg New Energy Finance, Industry growth slowed last year, to 20 percent. Part of the problem, for the still very young solar industry, is customer-acquisition. Many of them are reluctant to sign on to decades-long contracts with relatively small, little-known companies. The umbrella of big brand names can thus provide customer relationships and security.

Musk envisioned a company that sold Tesla electric cars, solar systems and its home battery unit at the same stores, giving consumers one-stop shopping for all of their clean-energy needs. In this sense, Tesla Inc. has dissolved the brand SolarCity and customers can purchase their solar panels at one of Tesla’s 300 stored worldwide.

Other companies, such as Sunrun Inc., now follow in the footsteps of Tesla: The panel manufacturer will try to sell panels in a recently completed deal through Comcast Corp., the biggest cable-TV company in the U.S. Gradually Tesla’s idea to combine solar, batteries and E-mobility doesn’t appear that crazy anymore!